At all times during his campaign against the forces of fever and infection Col. Gorgas has had to meet the opposition charge of extravagance and the waste of money. It has been flippantly asserted that it cost him $5 to kill a mosquito--of course an utterly baseless assertion, but one which is readily met by the truth that the bite of a single infected mosquito has more than once cost a life worth many thousand times five dollars. To fix precisely the cost of bringing the Zone to its present state of healthfulness is impossible, because the activities of the sanitary department comprehended many functions in addition to the actual work of sanitation. Col. Gorgas figures that the average expenses of sanitation during the whole construction period were about $365,000 a year and he points out that for the same period Chicago spent $600,000 without any quarantine or mosquito work. The total expenditures for sanitation when the Canal is finished will have amounted to less than one per cent of the cost of that great public work and without this sanitation the Canal could never have been built. That simple statement of fact seems sufficiently to cover the contribution of Col. Gorgas to the work, and to measure the credit he deserves for its completion. CHAPTER XV THE REPUBLIC OF PANAMA The Republic of Panama has an area of from 30,000 to 35,000 square miles, roughly approximating that of the state of Indiana. No complete survey of the country has ever been made and there is pending now a boundary dispute with Costa Rica in which the United States is arbitrator. The only other boundary, not formed by the sea, is that at which Panama and Colombia join. But Colombia says there is no boundary at all, but that Panama is one of her provinces in a state of rebellion. So the real size and bounds of the Republic must be set down as somewhat indeterminate. The circumstances under which Panama became an independent nation have been set forth in an earlier chapter. It is safe to say that with the heavy investment made by the United States in the Canal Zone, on the strength of a treaty with the infant republic, the sovereignty of Panama will be forever maintained against all comers--except the United States itself. There are political philosophers who think that the Isthmus state may yet be the southern boundary of the Great Republic of the North. For the present however Uncle Sam is quite content with the Canal Zone and a certain amount of diplomatic influence over the government of Panama. [Illustration: THE GORGE OF SALAMANCA]